Examples of molding methods used to seal semiconductor elements include transfer molding and compression molding. Transfer molding has problems of sealing resin-induced wire displacement, wire deformation, filling defects, and the like. Meanwhile, compression molding has problems that, when a liquid sealing resin flows into a mold, the sealing resin involves bubbles. In addition, since the thickness of the coating layer of the semiconductor element varies according to the amount of liquid sealing resin flowing into the mold, control of the balance between precise control of the amount of resin flowing in and the viscosity of the sealing resin is required. However, it is hard to control the valance.
Then, Japanese Unexamined Patent Application Publication No. 2011-258634A discloses using a laminated photosemiconductor sealing sheet provided with a sealing resin layer and a phosphor-containing layer to obtain a sealed piece via compression molding. However, the sealing resin layer and the phosphor-containing layer are each obtained by drying a solution obtained by dissolving a silicone elastomer and a modified silicone resin in an organic solvent, and do not involve a hot-meltable hydrosilylation reaction-crosslinkable silicone composition. Thus, it is difficult to control the shape of the seal.
Japanese Unexamined Patent Application Publication No. 2007-123915A discloses laminating an LED using a phosphor sheet of phosphor-containing silicone, but a hot-meltable hydrosilylation reaction-crosslinkable silicone composition is not used, and it is difficult to obtain a hemi-spheroidal lens- or dome-shaped seal.